Optimizing resolution for type 1 macular neovascularization detection in pachychoroid disease: A 3 × 3 vs 6 × 6 mm SS-OCTA comparative study

Purpose: To compare the effectiveness of 3 × 3 mm versus 6 × 6 mm swept source optical coherence tomography angiography (SS-OCTA) scan patterns in detecting and characterizing pachychoroid-associated macular neovascularization (MNV). Methods: We retrospectively analyzed 79 eyes from 79 treatment-naïve patients with pachychoroid-associated MNV using SS-OCTA. Both 3 × 3 mm and 6 × 6 mm scans were obtained on the same day. Two masked graders independently evaluated neovascular network area and presence of anastomoses. Results: Mean lesion areas were significantly larger in 6 × 6 mm scans compared to 3 × 3 mm scans (0.869 ± 0.868 mm² vs 0.699 ± 0.697 mm²; p = 0.005). However, analysis of anastomoses revealed superior detection with 3 × 3 mm scans, with 12 eyes (15.2%) showing anastomoses only in 3 × 3 mm scans compared to 4 eyes (5.1%) visible only in 6 × 6 mm scans (p = 0.021). Interobserver agreement was excellent for area measurements (ICC = 0.92). Conclusions: While 6 × 6 mm SS-OCTA scans demonstrate larger overall neovascular area measurements, the 3 × 3 mm scan pattern provides superior visualization of anastomoses and fine vascular details in pachychoroid-associated MNV. These findings suggest that 3 × 3 mm scans should be considered the preferred protocol for detailed evaluation of these lesions.